Composite container

ABSTRACT

A container of composite construction which comprises a widemouthed inner shell formed of seamless thermoplastic material in a generally frusto-conical configuration so that like shells are nestable in a compact stack, the sidewall portion of the shell being of relatively thin and fragile construction, and which further comprises an externally decorated, relatively stiff paperboard sleeve which is wound around the side wall portion of the shell and which is adhesively secured in face to face reinforcing contact therewith, the opposed ends of the blank from which the sleeve is formed each comprising a series of alternating recesses and protrusions which are interengageable with corresponding protrusions and recesses in the other end to accurately register the ends of the sleeve with respect to one another in a serpentine-shaped butt seam. In the preferred embodiment, the side wall of the inner shell is provided with a stacking shoulder immediately below the rim portion of the shell to facilitate denesting of nested shells and/or denesting of nested finished containers and, when the outer sleeve is joined to the inner shell by a water based or solvent-based adhesive, the stacking shoulder may advantageously be provided with a circumferentially spaced series of vent indentations to permit the escape of adhesive vapors from a stack of nested finished containers.

tlriite tates Patent [1 1 [52] US. Cl. 229/115 M, 229/45 [51] lnt. ClB65411 3/00 [58] Field of Search 229/15 B, 1.5 R, 229/45 [56] ReferencesCited UNITED STATES PATENTS 3,333,515 8/1967 McGlynn 229/15 B X3,215,325 11/1965 Shappell et al.. 229/15 B 3,094,240 6/1963 Wanderer229/15 B X 3,208,631 9/1965 Edwards 229/15 B X 3,277,220 10/1966 Plymaleet al... 229/15 B X 3,299,914 1/1967 Harmon 229/].5 B X 3,353,70711/1967 Eyles 229/15 B X 3,374,922 3/1968 Shelby.. 229/15 B X 3,471,07510/1969 Wolf 229/15 B 1,756,243 4/1930 Benson 229/45 X 3,199,757 8/1965McConnell 229/15 B Primary Examiner-Allen N. Knowles Att0rneyE. J.Holder et a1.

Amber Sept. 18, 1973 colwt'oslnm coNTAIINEn 57 ABSTRACT Inventor: 0Monticello, A container of composite construction which com- [73]Assignee: Owens-illinois, Hue, Toledo, Ohio prises a wide-mouthed innershell formed of seamless thermoplastic material in a generally frustoconical [22] Filed: July M, 1971 configuration so that like shells arenestable in a compact stack, the sidewall portion of the shell being ofrelatively thin and fragile construction, and which further comprises anexternally decorated, relatively stiff paperboard sleeve which is woundaround the side wall portion of the shell and which is adhesivelysecured in face to face reinforcing contact therewith, the opposed endsof the blank from which the sleeve is formed each comprising a series ofalternating recesses and protrusions which are interengageable withcorresponding protrusions and recesses in the other end to accuratelyregister the ends of the sleeve with respect to one another in aserpentine-shaped butt seam. In the preferred embodiment, the side wallof the inner shell is provided with a stacking shoulder immediatelybelow the rim portion of the shell to facilitate denesting of nestedshells and/or denesting of nested finished containers and, when theouter sleeve is joined to the inner shell by a water based orsolvent-based adhesive, the stacking shoulder may advantageously beprovided with a circumferentially spaced series of vent indentations topermit the escape of adhesive vapors from a stack of nested finishedcontainers.

7 Claims, 8 Drawing Figures PATENTEDSEPI 81975 SHEEI 1 BF 2 INVENTOR. vRALPH G. AMBERG AWKUQCAIS PATENTED 3.759.437

sum 2 or 2 INVENTOR. RALDH G. Amesrza QWQWMM ll coMPosiTE coNTAiNERGENERAL DESCRIPTION OF THE INVENTION As is pointed out in the copendingapplication Ser. No. 747,183, now abandoned of Stephen W. Amberg andRodney E. Ludder, which is assigied to the assignee of the application,a wide mouthed container with an externally decorated surface mayadvantageously be formed of composite construction with an undecoratedinner shell formed of seamless thermoplastic material and with an outerreinforcing sleeve formed by rolling a paperboard blank around the innershell and by adhesively securing the thus-formed sleeve to the innershell to form a unitary structure therewith. In such a case, thedecorative material desired by each concern which is interested inpacking its products in such containers may be placed on the outwardlyfacing surface of the sleeve, thereby making it possible to utilize anidentical or universal inner shell for all or a wide variety of suchcontainers, and thereby greatly simplifying the production schedulingand inventorying problems connected with the manufacture of such shells,especially when such shells are of nestable configuration. Additionally,the decorating problems involved in the manufacture of containers forthe purposes served by composite containers of the present invention maybe greatly simplified by the present invention, as the outer sleeve maybe'rapidly formed by severing the blank from a preprinted web or sheetcomprising a multitude of such blanks. In such case it is generallyconsiderably less expensive to impart high quality decorative materialto the web or sheet by known techniques, as by flexographic orrotogravure printing, which can not be employed if the decorating stepis done after the container is fonned and which is generally the mannerin which containers formed of unitary construction are decorated.Furthermore, as paperboard is generally a considerably less expensivematerial than the polymeric materials which are suitable for theformation of the inner shell of the composite container of the presentinvention, or the unitary containers of the prior art which are usefulfor similar packaging applications, an economic savings in materials canbe realized with the present'invention by constructing the inner shellwith a much thinner wall than that which a corresponding unitarycontainer would require for adequate rigidity and durability, and byutilizing the rigidifying properties of the associated outer sleeve toreinforce the inner shell. The substantial reduction in resin weightwhich can be obtained in the practice of the present invention, andwhich was in a known instance involving containers of 8 fluid ouncecapacity for packing yogurt, over 55% of the weight of a comparableunitary plastic container, makes it economically feasible to use moreexpensive resins which have superior properties relative to those whichcould otherwise be used.

In the manufacture of composite containers according to the aforesaidapplication Ser. No. 747,183, now abandoned, the outer sleeve waswrapped with its opposed ends joined in a lapped seam. The use of alapped seam for this purpose involves the usual problems oflongitudinally aligning or registering the end portions of the sleevewith one another so that the decorative material on the end portions ofthe sleeve is in registration. Likewise, the double thickness ofpaperboard in the seam region limits the compactness of the nestingarrangements for like finished containers of this type.

2. To overcome the foregoing problems of a lapped seam, the sleeve ofthe composite container of the present invention, may, in cases of smallcontainers where the added strength of a lapped seam is not required, besized so that the circumferential extent of all portions thereof areequal to or slightly less than the circumferential extent of thesidewall of the inner shell which is overlapped thereby, so that thesleeve can be wrapped with a butt seam. In a preferred embodiment of theinvention, the opposed ends of the blank from which the outer sleeve isformed are cut in a serpentine pattern with an alternating series ofprotrusions and recesses which are interengageable with corresponding orcomplementary recesses and protrusions in the other end so as to form aserpentine shapped butt seam in the rolled sleeve, and to thereby insurevery accurate registration of the decorative material in the portions ofthe sleeve adjacent such ends. Additionally, the irregularity in thebutt seam provided in this manner serves to inhibit the tearing of therelatively fragile underlying shell along a line extending throughtheseam, as might be caused when the container is subjected tocompressive loads of the magnitude encountered during capping.

For many of the end use applications of the present invention, it isdesirable that similar finished containers be nestable in. compactstacks with one another, and indeed, it is often desirable forconservation of inventorying, space during manufacturing that theinternal shells also be nestable with one another until it is de siredto finish the container by the affixing of outer sleeves thereto.Accordingly, in such instances the inner shell of such a container isconstructed with a sidewall which tapers upwardly and outwardly from thebottom or base portion of the shell to the rim portion thereof, and tofacilitate denesting of such shells from one another, or denesting offinished containers comprising such shells, each such shell is providedwith a stacking shoulder or ring near the rim portion thereof forengagement with the top of the rim of the shell or container into whichsuch shell or container is inserted during nesting. In instances wherethe sleeves of such containers are affixed to the shells thereof bymeans of a water-based or solvent based adhesive, such stacking shoulderor ring may be advantageously provided with a circumferentially spacedplurality of narrow indenta-.

tionsto form vent openings to permit residual adhesive moisture orvapors to escape from a stack of such nested containers. a

Accordingly, it is an object of the present invention to provide animprovedcomposite container. It is a fur ther object of the presentinvention to provide a composite container comprisinga seamless,thermoplastic inner shell with a relatively thin sidewall that isreinforcedly surrounded by a butt-seamed paperboard sleeve that issecured thereto and which bears all requisite printing or otherdecorative material on the outer surface thereof. It is a further objectof the present invention to provide a composite container which isnestable with similar composite containers and which com-. prises meansfor venting vapors from the adhesive used in joining the elements ofsuch composite containers from a nested stack of such containers.

For a further understanding of the present invention and the objectsthereof, attention is directed to the drawing and to the followingdescription thereof, the detailed description of the invention and theappended claims. I I V DESCRIPTION OF THE DRAWING FIG. 1 is a plan viewof a blank from which an element of the composite container of thepresent invention is formed;

FIG. 2 is an elevational view, partly in section, of another element ofthe composite container of the present invention;

FIG. 3 is a fragmentary elevational view, partly in section, depicting astep in the manufacture of the composite container of the presentinvention;

FIG. 4 is a fragmentary elevational view, partly in section, depicting astep subsequent to that shown in FIG. 1 in the manufacture of thecomposite container of the present invention;

FIG. 5 is an elevational view, partly in section, of a compositecontainer embodying the present invention;

FIG. 6 is a plan view of the composite container of FIG. 5;

FIG. 7 is an elevational view of a stack of similar nested containers ofthe type shown in FIG. 5; and

FIG. 8 is a fragmentary sectional view at an enlarged scale and taken online 8-8 of FIG. 7.

DETAILED DESCRIPTION OF THE INVENTION As is shown in FIG. l, the outerwrapper of a composite container according to the present invention isformed from a flat blank, shown generally at 11, of a suitable foldablesheetlike material such as paperboard or laminates of paperboard andmetal foil or plastic sheeting. The surface 11a of blank 11 which willserve as the outer surface of the completed container is provided withprinting and decorative material, shown generally at 12, which ispreferably, for economic reasons, applied by known high-speed techniquesto the web or sheet from which a multitude of identical blanks may besevered, prior to such severence. Blank 11 is sized and shaped toconform, when assembled, to the configuration of the associated innershell of the composite container in which it is to be used, ashereinafter described.

Thus, in the illustrated embodiment of the invention, in which thecomposite container is to be of generally frusto-conical configurationfor nestability, blank 11 is of generally trapezoidal configuration withthe top and the bottom edges 13 and 14 thereof having an arcuateconfiguration. The ends 15 and 16 of blank 11, as shown, comprise analternating series of protrusions 15a and 16a, respectively, andrecesses 15b and 16b, respectively, for purposes which will behereinafter described more fully.

The other element of the composite container of the present invention isa generally cup-shaped inner shell, shown generally at 21, which isformed of a thermoplastic material which is compatible with the productto be packaged therein, for example, polystyrene, polypropylene,polyethylene or any of a wide variety of other polymeric materials.Shell 21 is preferably of seamless construction, and such a shell may beformed from the suitable resins as mentioned above by known techniques,such as by vacuum forming.

As is shown in FIG. 2, shell 21 comprises a rim portion 22 which definesthe upper open end or mouth thereof, a closed base portion 23 and asidewall portion 24 which extends upwardly and outwardly from baseportion 23 to rim portion 22.

Because it may be desirable to compactly store a multitude of similarshells 21 after the shell manufacturing stage and before the containerassembling stage, the side wall portion 24 of each shell isadvantageously provided with an outwardly projecting andcircumferentially extending stacking shoulder 25, the lower portion ofwhich is adapted to rest on the top of the rim portion of a similarshell in which such a shell may be inserted in a stack of such nestedshells to maintain sufficient space between adjacent shells tofacilitate denesting of the shells when desired. Stacking shoulder 25 incertain situations, as hereinafter described more fully, mayadvantageously be provided with a circumferentially spaced series ofnarrow recesses or indentations 25a.

A composite container of the present invention may be formed from apaperboard blank 11 and a thermoplastic shell 21 in any suitable way,but it has been found that the assembly may be expeditiouslyaccomplished by the use of a fixture, shown generally at 31 in FIGS. 3and 4, which has an inner cavity defined by a surface 32 whichcorresponds to the outer surface of a sleeve 11' formed from blank 11when ends 15 and 16 thereof are brought together. Blank 11 is,accordingly, inserted into fixture 31 and is continually advanceddownwardly thereinto until the lower edge of blank 1 1 rests on a thinradially extending shoulder 33 at the bottom of wall 31, therebybringing the protrusions and recesses 16a and 16b of edge 16 intointerengaging or interlocking relationship with the correspondingprotrusions and recesses 15b and 15a of edge 15. After the completion ofthis step, which is shown in FIG. 3, a shell 21, to which has previouslybeen applied a suitable adhesive 26 to at least a major surface portionof the exterior side wall portion 24 which will contact the innersurface of the sleeve formed from blank 11, and preferably tosubstantially all of such surface portion, is advanced into the fixturecontaining such sleeve and is retained therein until adhesive 26 sets tofirmly secure or bond the sleeve to the side wall of the shell in arigid, reinforced relationship. Thereupon, the container comprising suchbonded elements may be removed from the fixture. In the practice of theinvention, as described, it is desirable to maintain the extreme,inherently rounded corner at the juncture of the side wall and the baseof the shell 21 at an elevationslightly below the lower edge of sleeve 11 in the assembled container. This is the reason for the incorporationof a shoulder 33 above the elevation of the main portion 34 of thebottom surface of fixture 31 against which the base 23 of shell 21 isbrought during assembly.

present invention, formed in the manner heretofore described or in anyother suitable manner, is shown generally at 41 in FIGS. 5 and 6, thedecorative material on the outer surface of sleeve 111' being omittedfor the sake of simplicity, with other visible portions of the Acompleted composite container according to the shortly after themanufacture thereof, when the adhesive is of a water-based orsolvent-based type, some of the water or solvent may remain in theadhesive at the time such stack is formed. In these situations,indentations 125a in the stacking rings 125 of the shell portions 121serve to provide an escape path for the escape of the moisture orsolvent vapors from the stack, as is shown in MG. 8.

To obtain the full economic advantages of the present invention, it isimportant that the strength and rigidity of the side wall of thecomposite container be de rived largely from the paperboard sleeve 11,rather than from the inner shell 21. To this end, it is recommended thata relatively sturdy grade of paperboard be used for the outer sleeve,and that the thickness of the side wall of the inner shell be very lightand fragile. For example, satisfactory composite containers according tothe present invention have been made for packaging yogurt in 8 fluidounce capacity using an inner polystyrene shell of a weight of 10 lbs.per thousand shells (compared to a weight of 23 lbs. per thousandunitary polystyrene containers for a comparable application) and apaperboard sleeve of a thickness of 10 mils (0.010 inch).

Composite containers according to the present invention will, of course,ordinarily be closed after filling with the product to be packedtherein, but such closing means have not been described, as knownclosing techniques are adaptable to a container as described.

The best mode known to me to carry out this invention has been describedabove in terms sufficiently full, clear, concise and exact as to enableany person skilled in the art to make and use the same. It is to beunderstood, however, that it is within my contemplation that certainmodifications of the above-described mode of practicing the inventioncan be made by a skilled artisan without departing from the scope of theinvention and it is, therefore, desired to limit the invention only inaccordance with the appended claims.

lclaim:

1. A composite container comprising, in combination: an inner shellformed of a thermoplastic material and including a rim portion definingthe open end of said container, a base portion, and a surrounding sidewall portion extending'upwardly from said base portion to said rimportion; and a-sleeve formed from a doubleended blank of paperboardstock which is decorated on one surface thereof, said sleeve being woundaround the side wall portion of the inner shell with the other surfaceof the sleeve covering a major portion of said side wall portion andbeing secured thereto in reinforcing relationship, the circumferentialextent of all portions of said sleeve being no greater than thecircumferential extent of the portion of the side wall of the innershell which is immediately adjacent thereto so that no portion of oneend of the blank from which the sleeve is formed overlaps any portion ofthe other end thereof in the finished container, the opposed ends of thesleeve each comprising a series of alternating protrusions and recesseswith the protrusions and recesses on each end being so arranged as to beinterengageable with corresponding recesses and protrusions of the otherend to form a serpentine shaped butt seam between the ends of the sleeveand to thereby insure accurate registration of the decorated portions ofthe outer surface of the sleeve which are proximate to said opposed endsthereof.

2. A composite container according to claim 1 wherein the side wallportion of the inner shell extends upwardly and outwardly from the baseportion of the shell to the rim portion thereof whereby said shell isnestable with similarly shaped shells;

3. A composite container according to claim 2 wherein said side wallportion of said shell comprises a stacking shoulder immediately belowthe rim portion of the shell, said stacking shoulder being engageablewith the rim of another similarly shaped shell into which said shell maybe inserted in nested relationship to permit rapid denesting of saidshell when desired.

4. A composite container according to claim 3 wherein a major portion ofsaid other surface of the sleeve is adhesively joined to the side wallportion of the shell in face to face contact therewith.

5. A composite container according to claim 4 wherein said stackingshoulder comprises a plurality of circumferentially spaced ventindentations therein to permit the escape of adhesive vapors from astack of nested and similarly shaped composite containers with whichsaid composite container may be nested.

6. A composite container according to claim 1 wherein said sleeve issecured to said shell by means of an adhesive which adhesively joins atleast amajor portion of the inner surface of-t he sleeve to theadjoining portion of the sidewall of the shell.

7. A composite container according to claim 6 wherein substantiallythe-entire inner surface of the sleeve is adhesively joinedto theadjoining portion of the side wall of the shell.

1. A composite container comprising, in combination: an inner shellformed of a thermoplastic material and including a rim portion definingthe open end of said container, a base portion, and a surrounding sidewall portion extending upwardly from said base portion to said rimportion; and a sleeve formed from a double-ended blank of paperboardstock which is decorated on one surface thereof, said sleeve being woundaround the side wall portion of the inner shell with the other surfaceof the sleeve covering a major portion of said side wall portion andbeing secured thereto in reinforcing relationship, the circumferentialextent of all portions of said sleeve being no greater than thecircumferential extent of the portion of the side wall of the innershell which is immediately adjacent thereto so that no portion of oneend of the blank from which the sleeve is formed overlaps any portion ofthe other end thereof in the finished container, the opposed ends of thesleeve each comprising a series of alternating protrusions and recesseswith the protrusions and recesses on each end being so arranged as to beinterengageable with corresponding recesses and protrusions of the otherend to form a serpentine shaped butt seam between the ends of the sleeveand to thereby insure accurate registration of the decorated portions ofthe outer surface of the sleeve which are proximate to said opposed endsthereof.
 2. A composite container according to claim 1 wherein the sidewall portion of the inner shell extends upwardly and outwardly from thebase portion of the shell to the rim portion thereof whereby said shellis nestable with similarly shaped shells.
 3. A composite containeraccording to claim 2 wherein said side wall portion of said shellcomprises a stacking shoulder immediately below the rim portion of theshell, said stacking shoulder being engageable with the rim of anothersimilarly shaped shell into which said shell may be inserted in nestedrelationship to permit rapid denesting of said shell when desired.
 4. Acomposite container according to claim 3 wherein a major portion of saidother surface of the sleeve is adhesively joined to the side wallportion of the shell in face to face contact therewith.
 5. A compositecontainer according to claim 4 wherein said stacking shoulder comprisesa plurality of circumferentially spaced vent indentations therein topermit the escape of adhesive vapors from a stack of nested andsimilarly shaped composite containers with which said compositecontainer may be nested.
 6. A composite container according to claim 1wherein said sleeve is secured to said shell by means of an adhesivewhich adhesively joins at least a major portion of the inner surface ofthe sleeve to the adjoining portion of the side wall of the shell.
 7. Acomposite container according to claim 6 wherein substantially theentire inner surface of the sleeve is adhesively joined to the adjoiningportion of the side wall of the shell.